the actual problems of microworld physics the actual problems of microworld physics gomel, belarus,...

The Actual Problems of Microworld Physics Gomel, Belarus, July 22 - August 2, 2013

The new electro-nuclear method and scheme of energy production and transmutation of radioactive

waste components of nuclear power

S.TyutyunnikovJoint Institute for Nuclear Research, Dubna, Russia

Joint Institute for Nuclear Research, Dubna, Russia; CPTP «Atomenergomash», Moscow, Russia;

INP, Rez near Praha, Czech Republic; IAE, Swierk near Warzhawa, Poland; JIENR Sosny near Minsk, Belarus;

Stepanov IP, Minsk, BelarusKIPT, Kharkov, Ukraine; INRNE, Sofiaя, Bulgaria; ESU, Erevan, Armenia;

Uni-Sydney, Sydney, Australia; Aristotele Uni-Saloniki, Tessaloniki, Greece;

IPT, Almaty, Kazahstan; IPT, Ulanbaatar, Mongolia; INS Vinca, Belgrad, Serbia

Bhabha ARC, Mumbai, India; Gesellschaft for Kernspektrometrie, Gemany;

Leipunsky IPPE, Obninsk, RussiaFZJ, Julich, Germany

Polytechnic Institute, Praha, Czech Republic; Dubna University, Dubna, Russia;

IAR AS, Kishinev, Moldova; UzhNU, Uzhgorod, Ukraine.

Gomel, July 22 - August 2, 2013

Workshop Collaboration “E + T RAW” (“Energy plus Transmutation of Radioactive Wastes”)

2011, November


Content

Basic principles of classical nuclear energy

Traditional nuclear fission ADS technology, the principles,

achievements and prospects The physical basis of relativistic

nuclear energy and the experimental results

Conclusion Gomel, July 22 - August 2, 2013


Introduction

Stocks explored oil and gas provide energy fuel for 30-50 years.

Explored reserves of coal - for 200-300 years. The share of nuclear energy in overall energy

balance of the Earth - 6%. Classical nuclear power, founded on the division

of U235, Pb239 has several problems: Limited stocks of fissile material - at 20-50 years. Continuous operating time of nuclear waste.

Traditional nuclear fission

● Nuclear energy is produced whenever a light nucleus is undergoing fusion or a heavy nucleus is undergoing fission.● Today’s nuclear energy is based on U-235, 0.71 % of the natural Uranium, fissionable both with thermal and with fast neutrons.● At the present consumption rate (≈6% of primary energy), U reserves are about comparable with those of Oil and NG.● In the Sixties, ”Atoms for Peace” had promised cheap, abundant and universally available nuclear power, where the few “nuclear” countries would ensure the necessary know-how to the many others which had renounced nuclear weaponry.● Today, the situation is far from being universally acceptable: the link between peaceful and military applications has been shortened by the inevitable developments and the corresponding widening of the know-how of nuclear technologies.● For nuclear energy to become freely and more abundantly available in all countries, some totally different but adequate nuclear technology must be developed.



New, virtually unlimited forms of nuclear energy

● Particularly interesting are fission reactions in which a natural element is firstly bred into a readily fissionable element.

Energy Amplifier

Gen-IV

● The main advantage of these reactions without U-235 is that they may offer an essentially unlimited energy supply, during millennia at the present primary energy level, quite comparable to the one of Lithium driven D-T Nuclear Fusion.● However, they require substantial developments since : ➩two neutrons (rather than one) are necessary to close the main cycle➩the daughter elements (U-233 and/or Pu-239) do not exist in nature but they can be generated after initiation


• The problems of rapidly growing energy consumption in the world can not be solved without the use of nuclear energy.• The key issue here is the availability of an adequate supply of nuclear fuel. In the long term aspect, the use of such materials as enriched 235U or artificial 239Pu can not solve the problem of global energy.• Indeed, they receive is very energy intensive, and the total value is rather limited and certainly does not exceed the forecast amount of hydrocarbon fuel.• So only involvement in the production of energy is practically unlimited reserves of natural (depleted) uranium and thorium can provide long-term prospects for nuclear energy.


Structure of an irradiated PWR fuel element

PWR fuel element = 500 kg U before Irradiation

Valuable Materials HL Waste

Uranium : 475 kg(95 %)

Plutonium : 5 kg( 1 %)

Fission Products: 20 kg (4 %)

Minor Actinides : ~ 500g (0.1 %)

The unresolved problem of disposing of spent nuclear fuel, containing the accumulated long-lived radioactive fission products and minor actinides - a major obstacle for the development of conventional nuclear power.

To date, spent fuel assemblies (FAs) containing spent nuclear fuel, are not subject to processing, but simply placed in the complex-site storage of existing nuclear power plants, awaiting the development of effective technologies for processing and creation of appropriate capacity. The main way of reducing the activity is implemented simply by their long exposure.

Loading VVER-1000 is ~ 80 t UO2 (~ 70 tons of uranium). Over 60 years of operation one unit will be unloaded ~ 1600 tons of SNF, containing a total of ~ 16.6 tons of transuranic elements, of which ~ 16.0 tones - the plutonium isotopes .

With today's technology in the processing of 1 ton of spent nuclear fuel (about 0.1 m3) produced ~ 45 m3 of liquid high level radioactive waste, about 150 m3 of medium-and low-level ~ 2000 m3.

In the closed nuclear fuel cycle (not yet implemented) is expected education annually as a result of processing up to 25 m3/GW high-level waste, intermediate level and 50-100 m3/GW 700 m3/GWlow-level waste.

The repository is Yucca Mountain (USA), capacity 70 000 tons of spent nuclear fuel has been allocated ~ 96.2 billion. I.e. cost of SNF is ~ 1374 $/kg only capital costs, not including transportation and maintenance.

The cost of fuel loading in three years, the VVER-1000 ~ 94 million, or ~1175$/kg.

Thus, the SNF is considerably more expensive than fresh fuel.Gomel, July 22 - August 2, 2013


√ Direct disposal of the over all nuclear wastes

Radiotoxicity


√ Separation and transmutation of 99.9% of Pu and U

Radiotoxicity


√ Separation and transmutation of 99.9% of Pu, U and MA

√ Achievement:

Disposal times are shifted from geological to historical time scales in nuclear waste disposal.

Radiotoxicity

Transmutation with present technology

Fast Reactors LWR Reactors

Innovative Concepts

Innovative

Gene IV Reactors


Fundamental, ineradicable weaknesses of today's nuclear energy technologies:

1) use as nuclear fuel, fissile materials – 235U, in the long term 239Pu and 233U;

2) work with fission spectrum neutrons (average energy spectrum - 2MeV, the maximum - 10 MeV);

and as a result, work on the basis of a controlled fission chain reaction.

Consequence



4 ineradicable in today's nuclear energy technology issues:

resulting from the first three – the problem of withdrawal power blocks of modern nuclear power plants

theoretical possibility of a critical accident;

use of working hours and "bomb" material - the actinides, i.e., problem of non-proliferation;

continuous operating time of long-lived radioactive waste;

1

2

3

4

Consequence


The physical aspects of electro-nuclear energy production method are actively studied today in many scientific centers all over the world: USA, Germany, France, Sweden, Switzerland, Japan, Russia, Belarus, China, India etc. Most activities are concentrated on the classical electro-nuclear systems – Accelerator Driven Systems (ADS) – based on spallation neutron generation, with a spectrum harder than that of fission neutrons, by protons with an energy of about 1 GeV in a high-Z target. These neutrons can also be used for generating nuclear energy in the active zone having criticality of 0,94-0,98 and surrounding the target.

The large national projects devoted to the creation of industrial ADS demonstration prototypes are implemented in Japan (JPARC), USA (RACE), the joint European project EUROTRNS is carried out.

The main advantage of electro-nuclear technology, as compared to conventional reactor technologies, is that subcritical active core and external neutron source (accelerator and neutron-producing target) are used. This advantage doesn’t provides only intrinsic safety of the system but also makes it possible to obtain high fluxes of high energy neutrons independent of fission neutrons of the subcritical assembly material. The high-energy neutrons are an ideal tool to induce fission in most trans-uranium isotopes and thus transmute most of the dangerous radioactive waste from nuclear power production and other sources.

ADS - technology

Accelerator Driven Systems

Proton (Linear) Accelerator E ~ 1 GeV, I ~ 15-100 mA


Critical (reactor) and sub-critical (energy amplifier) operation



The need for a new concept: an Accelerator driven system

● This very small neutron excess is essentially incompatible with the requirements of any critical reactor without U-235. An external neutron source must be added to ensure the neutron inventory balance. This is both true for Fission (Th and/or Depleted U) and D-T Fusion starting from Lithium.● The development of modern accelerators has permitted the production of a substantial neutron flux with the help of a proton driven high energy spallation source.● Let Keff be the neutron multiplication coefficient of an ADS (Keff =1 for a critical reactor). In a “sub-critical” mode, Keff <1 neutrons are produced by a spallation driven proton beam source and multiplied by fissions. The nuclear power is then directly proportional to the proton beam power with a gain G:

G = χ ≈ 2.1.÷ 2.4 for Pb - p coll. > 0.5 GeV

G = 70-80 for Keff=0.97 and G = 700-800 for Keff = 0.997 (very large)


• But in this experiment the massive uranium target ( ~3.5 tones) was embedded into light water moderator. As consequence the neutron spectrum inside of active core was practically fully thermalized and neutron multiplicity coefficient Keff this system was near 0.9.

• In these circumstances in spite of rather promising GBP~30 it is difficult to implement "burning" of the base core material (natural uranium or thorium) because of their high fission threshold.

• And actually proposed EA options must move on to the enriched fuel!?

Problems of natural uranium and thorium use


SPATIAL DISTRIBUTION OF THE NEUTRON FLUX

Spatial distribution of the neutron flux depending on the value of k.

Neu

tron

flux

dist

ributi

on (a

rbitr

ary

units

)

Distance from the source (mm)

Comparison of the neutron flux distribution between measured data and Monte Carlo calculations carried out in the "source mode" with EAMC and MCNP-4B, and in the "reactor mode" with MCNP-4B.


Main result of the FEAT experiment(S. Andriamonje et al.,CERN/AT/94-45(ET))

A prolific neutron source: the proton spallation in a heavy Z

Modern proton accelerators on a heavy Z target (Lead) produce a very large number of neutrons. For a proton energy of 1 GeV and 1.5 GWatt thermal power we need:

➩2.7 1020 fission/s (Keff = 0.997, G=700 )➩3.8 1017 spallation neutrons/s (30 n/p)➩1.3 1016 protons/s➩Current: 2.12 mA

Compare: PSI proton cyclotron:590 MeV, 72 MeV injection 2mA, 1 MWatt



Accelerator requirements and reliability

● The spallation target is the most innovative element of the Energy Amplifier.● High currents are within the possibilities of modern accelerators, either Cyclotrons or superconducting LINACs.● Reliability is the most important new aspect of an otherwise within the state of the art realization.● It should be easily achieved through redundancy of the separate components: no more than few beam trips per year

Cyclotron


Principle of operation of the Energy Amplifier● The process is based on two steps:

➩Non fissile Thorium is transformed into fissile U-233 with the help of a first neutron:➩Fissile U-233 is fissioned by a second neutron, with large energy production the emission of 2.3 new additional neutrons which continue the process.

● A particle accelerator is supplying the missing neutron fraction and it controls the energy produced in the reaction.● At the end of a cycle the fuel is reprocessed and the only waste are Fission Fragments Their radio-activity is intense, but limited to some hundred years.● Actinides are recovered without separation and are the “seeds” of the next load, added to fresh Thorium.● The cycle is “closed” in the sense that the only material inflow is the natural element and the only “outflow” are Fission Fragments.

Motivation of RNT (relativistic nuclear technology)

ADS is considered now as tool for the transmutation of the long-lived components of radioactive wastes (RAW) and in principle for the solution of global energy problems.

This work is aimed at study of the physicals properties of the ADS with quasi-infinite size active core (AC) from natural uranium irradiates by the pulsed p/d beam of (1-10) GeV energy.

The long-range goal is the study of the possibilities of such systems with maximally hard neutron spectrum inside of AC to realize so called Relativistic Nuclear Technology (RNT) for transmutation RAW and energy production due to burning of AC material.

Important aim of the experimental program is to provide comprehensive benchmark data set for verification and adjustment of INC models and transport codes.


Physical substantiation for investigation of new schemes of electronuclear power production and transmutation of long-lived radioactive wastes based on nuclear relativistic technologies is presented. “E + T RAW” (“Energy plus Transmutation of Radioactive Wastes”) is aimed at complex study of interaction of relativistic beams of Nuclotron-M with energies up to 10 GeV in quasi-infinite targets.

Feasibility of application of natural/depleted uranium or thorium without the use of uranium-235, as well as utilization of spent fuel elements of atomic power plants is demonstrated based on analysis of results of known experiments, numerical, and theoretical works.

“E + T RAW” project will provide fundamentally new data and numerical methods necessary for design of demonstration experimental-industrial setups based on the proposed scheme.

Physical basis of relativistic nuclear technology


Еp,GeV

< Е >, MeV

Еkin,MeV

Еkin / Еp, %W,

MeVW / Еp, %

0,994 8,82 213 21,3 382 38,2

2,0 11,6 513 25,6 822 41,1

3,65 13,7 1106 30,3 1670 45,6

Estimates power amplification coefficient for proton beam incident on quasi-infinite target from metallic natural uranium.

Ер, GeV Initial КPA Equilibrium КPA

0,66 7,4 40

1,0 12,0 70

10,0 22,0 130

Energy characteristics of neutron radiation leaving a limited Ø20×60 cm lead target depending on protons energy

(obtained in the complex experimental group V.I .Yurevich, executed in LHEP)

Here, < Е > is the average neutron energy, Еkin is the total kinetic energy of neutron radiation, Еp is the proton energy, and W

is the energy of the proton beam spent for neutron production. It can be seen from Table 2 that the average neutron energy, the kinetic neutron energy Е kin, and the proton beam energy W

spent for neutron production increase with increasing beam energy. The fraction of primary proton energy spent for neutron production for a proton energy of ~ 660 MeV is ~ 20 % according to our estimates of data [4]. It follows from [10] that for Еp ≈ 1

GeV it increases to 38,2%, reaching almost 46 % for 3,65 GeV. The extrapolation of this dependence to Еp = 10 GeV results in

the following estimate of this fraction: 60% (see [11] for details). Note that the growth of the ratio W/Еp is to a large extent

connected with the growth of meson production with increasing incident proton energy.




To a question about the expected energy gain G ofRNT-reactor

- Primary proton Ep= 10 GeV

neutrons

~ 66%

heat loss

~ 34%

neutrons En= 6,6 GeVequivalent

~ 6600of neutrons with En= 1 MeV

Fission threshold 238U

(1 GeV= 1000 MeV)

6600n0 0,2GeV(200MeV)=1320GeV G=1320 GeV / 10 GeV = 132

132 >> 5 > 3,3

Gain power factor in the RNT - scheme


The results of the estimates and the experiments show that in the scheme

NRT we have the opportunity to carry out with a hard neutron spectrum, having a large enough component of the far abroad fission spectrum throughout its life cycle.

Hard neutron spectrum in the volume of active zone RAW-system ensures efficient treatment all threshold of actinides.

Moreover, for all treatment actinides there is shift of the elemental composition of the fission fragments of nuclei in the isobaric chains in the direction of short-lived or stable neutron-deficient nuclei. For example, instead of generation a long-lived 129I, formed stable isotope 129Xe.

In addition, this spectrum provides an intensive course of reactions of type

(n, xn), which leads to a shift of the integral of the fission products in the direction of short-lived neutron-deficient nuclei. For example, as a result of reactions (n, 2n), (n, 3n) one of the most dangerous isotopes from the spent fuel - a long-lived 90Sr - processed (transmuted) in the short-lived 89Sr or stable 88Sr.

Finally, the tightening of the neutron spectrum leads to an additional suppression of the neutron capture reaction and significantly reduced operating time more long-lived radioactive materials.



Existing facility of Nuclotron M

E&T


The main parameters of Nuclotron-M

Deuterons beam parameters.March 2012

Track density distribution by E= 1 GeVMarch 2012Itot=1.9·1013

Track density distribution by E= 8 GeVMarch 2012Itot=3.7·1012


The setup "Quinta" on the irradiation position (December 2011 - March 2013)



Nuclotron session in November-December 2012

Professor I. Zhuk Professor A. Baldin


Construction of “Quinta” complex on the base of natural

uranium.

Three systems of entering beam monitoring were developed – • Two systems are based on wire and proportional

chambers with wide dynamic range and high spatial resolution.

• Method of absolute monitoring is based on Al and Cu activation taking into consideration different measurement modes.

In collaboration with the Radium Institute of the RAS the method

of TPC detectors for neutron flow study in wide region of spectrum

was mastered.

The method of planar silicon detectors for neutron flow

measurement was elaborated.

Prerequisites for the transition to quasi infinite target “Buran”

were created.

In the framework of the project the following tasks were accomplished:

General view of the beam monitoring systems

Since the aim of the experiments was to measure the absolute yield of the reactions under study it was required to create secure interchangeable systems of beam intensity monitoring. Some of the held measurements required knowledge of time structure of each pulse of accelerator and beam intensity variation during the session of irradiation. Therefore, besides commonly used methods of off-line monitoring integral number of deuterons incident on the target, it was necessary to develop on-line systems providing control of shape, intensity and time dependence of accelerator pulses. Being proposed to operate at considerable variation of beam intensity such a system should have wide dynamic range (105÷1012 ion/sec) and high (± 0,2 mm) precision of beam positioning on the target. For this purpose there were developed and successfully tested in experiments two independently operating position-sensitive ionization chambers, operating in required dynamic range.


Results of the measurement of intensity, shape and position of beam incident on the target with use of two monitoring systems. Relative accuracy of ±5% in intensity was achieved for the systems of beam

diagnostics.



Measuring the hardness of the neutron spectrum using of TFBC-detector

The measurements of the neutron spectrum using the activation technique

The measurements of neutron leakage from the set-up “Quinta” by passive silicon detectors and scintillation detector DEMON

The main measurements of nuclear-physical parameters of set-up "Quinta"


TFBC monitor of neutron or proton fluxes

The principle of detection is based on an electrical breakdown caused by a fission fragment that passes through a thin silicon dioxide layer. The breakdown is followed by explosive vaporization of a small part of the silicon dioxide layer and the metal electrode area. The breakdowns are non-shorting, i.e., they leave no permanent conducting path between the electrode and the silicon base.

FISSION CROSS SECTIONS


EXPERIMENTAL SETUP AT VESUVIOELECTRONICS AND DATA ACQUISITION SYSTEM

A direct signal from a p-type TFBC at 50 Ohm (upper line) and the corresponding NIM signal after a discriminator LeCroy 4608 (lower line)

Direct signals from an n-type TFBC at 50 Ohm (upper line) and after amplification by a fast linear amplifier Phillips Scientific 776 (lower line)



Sensitivity of natU/209Bi ratio to high energy end of neutron spectrum


Location TFBC and passive detectors along the perimeter of “Quinta”


Ratios of natU/209Bi (n,f)-reaction rates( black – inside of TA QUINTA, red – on the surface)

Energy spectrum of leakage neutrons becomes more “harder” with increase of deuteron energy !


Experimental data on the relationship natU (n,f) / 209Bi (n,f) (TPS) on the surface of the lead assembly.

(The distances to positions 1-2 are measured from the beam axis, for positions 3-7 (and 11-12) along the Quinta - from the corners of the

assembly, for positions 8-10 from the beam axis)

The ratio of number of fission natU(n.f) / 209Bi(n,f) along the side of Quinta

(data for 0.66 GeV/A and 4 GeV/A is not displayed, but the trend - the same)

natU (nf) / 209Bi (n, f)

Group A. Smirnov (Radium Institute)


Neutron spectrum modified to fit experimental ratio natU/209Bi (n,f)-reaction rates at QUINTA surface


Location of samples 6 GeV experiment

Yttrium Activaction detectors

Sample Material: Y-89 Reaction Threshold Energy Half Live

Time

(n,2n) MeV 11,5 106,65d (n,3n) MeV 20,8 79,8 h (n,4n) MeV 32,7 14,74 h (n,5n) MeV 42,1 2,68 h (n,6n) MeV 54,4 39,5 m


Arrangement of the 89Y detectors on the detector plates in the Quinta Assembly

Longitudinal view of the Quinta assembly

R80 R80

R40R50

BEAM AXIS BEAM AXIS

DETECTOR PLATE 0 DETECTOR PLATES 1, 2, 3, 4, 5

Yttrium detectors location on the detector plates.



Average neutron flux densities per deuteron for the three deuteron beams.

Average neutron flux density per deuteron in the third detector plane (where maximum occurs) and radius 4 cm for deuteron beam energy 2.0, 4.0 and 6.0 GeV compared with the Monte Carlo simulation using MCNPX 2.6 code. (March 2011)

0 20 40 60 80 100Neutron energy [M eV]

2x10 - 4

4x10 - 4

6x10 - 4

8x10 - 4

Ave

rage

neu

tron

flu

x de

nsity

per

deu

tero

n[1

/(cm

2 M

eV d

eute

ron)

Th ird detector p lane, radia l posit ion 4cm .Deuteron beam energy

Exper. 6 G eVExper. 4 G eVExper. 2 G eVM C N PX , 6G eVM C N PX , 4G eVM C N PX , 2G eV


56

N[59Co(n, 2α+4n)48V]/N[59Co(n, 2n)58Co]

CSeff > 100 MeV

47.6 MeV Threshold

CSeff 15÷40 MeV Eth = 10.6 MeV

0,90

0,95

1,00

1,05

1,10

1,15

1,20

1,25

1,30

1,35

0 2 4 6 8 10

Deuteron Energy

48V / 58Co

Spatial distribution of density of (n,f), (n,γ) and (n,xn) reactions was studied using activation of natural uranium foil (Ø 10 mm, 1 mm thick) placed on each detector plate at distances of R = 0; 4; 8 and 12 cm from the beam axis. Nf (R, Z) reaction numbers were defined according to the average yield of 97Zr (5,42%), 131I (3,64%), 133I (6,39%), 143Ce (4,26%) fission fragments, while Plutonium nucleus production NPu (R, Z) – according to the 239Np isotope yield in the chain:

238U(n,γ)239U β- (23,45 min) →239Np β- (2,36 d) →239Pu

Distribution of density of 238 U(n,2n)237U β- (6,75 d) reactions was studied on the base of 237U isotope activity.

Independent Nf (R, Z) values were measured with Solid-state Track Detectors (STD) having converters of natural uranium.

“Quinta” target cross-cut

900

beam window150×150

lead shield

d 0

Y

Z

114

120

r 40

262

393

131

17 17 17 17

524

655

700

Section U-238

channels formounting anddismantling of

detector plates

Fig. 1Geometry of the uranium targets at the "Quinta"

Z =0

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1GeV M12

4 GeV M12

8 GeV M12

Z =367.5

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1 GeV M12

4 GeV M12

8 GeV M12

Z =612.5

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1 GeV M12

4 GeV M12

8 GeV M12

Z =0

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1 GeV M12

4 GeV M12

8 GeV M12

Z =367.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1 GeV M12

4 GeV M12

8 GeV M12

Z =612.5

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1GeV M12

4 GeV M12

8 GeV M12

Z =0

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1GeV M12

4 GeV M12

8 GeV M12

Z =367.5

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1 GeV M12

4 GeV M12

8 GeV M12

Z =612.5

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1 GeV M12

4 GeV M12

8 GeV M12

Z =0

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1 GeV M12

4 GeV M12

8 GeV M12

Z =367.5

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1 GeV M12

4 GeV M12

8 GeV M12

Z =612.5

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

-10 10 30 50 70 90 110 130 150

R, mm

Nx10-5

1GeV M12

4 GeV M12

8 GeV M12

The two-dimensional distributions of Nf (R,Z) numbers (normalized to 1 cm3, 1 deuteron and 1 GeV) measured in March 2012 at energies of 1; 4 and 8 GeV. (a, b and c, respectively).

The radial distribution of Nf (R,Z) and NPu (R,Z) numbers (left and right side of the figure) normalized to 1 kg of uranium, 1 deuteron and 1 GeV and measured in March 2012 at deuteron energies of 1; 4 and 8 GeV.

a b cGomel, July 22 - August 2, 2013


Date Ed = 1 GeV Ed = 2 GeV Ed = 4 GeV Ed = 6 GeV Ed = 8 GeVMeasuring method - ТТD

Integral number of fissions03.11 11 ±1.9 9.4 ±1.7 9.6 ±1.712.11 11.8 ± 2.0 8.2 ±1.5 10.0 ±1.703.12 8.9 ±1.5 8.1 ±1.5 9.2 ±1.6

Activation methodIntegral number of fissions

03.11 (8.8±0.4) ±1.0 (8.8± 0.4) ±1.0 (8.3±0.4) ±0.912.11 (10.6±0.5) ±1.1 (8.5± 0.4) ±1.0

03.12 (10.2±0.5) ±1.1 (9.6± 0.4) ±1.0 (9.4±0.5) ±1.0

12.12 (10.5±0.5)±1.1 (10.3±0.5)±1.1 (9.3±0.5)±1.0

Integral number of produced 239Pu nuclei 03.11 (7.0±0.3) ±0.8 (7.2±0.4) ±0.8 (6.9±0.3)±0.7

12.11 (11.8±0.6)±1.2 (10.8±0.5)±1.1

03.12 (11.3±0.6)±1.2 (11.0±0.5)±1.1 (10.2±0.5)±1.1

12.12 (12.5±0.7)±1.3 (12.2±0.7)±1.3 (10.3±0.5)±1.1

totfN

totfN

Integral numbers of ( ) fissions and 239Pu nuclei produced ( )(per 1 deuteron and 1 GeV)

totfN tot

PuN


Radiation hardness of silicon detectors

A. The detector leakage current increases linearly with hadrons fluence:

ΔΙ=αI⋅I ⋅ Φ ⋅ V

Φ − fluence, V − the detector bulk,αI =(5±1) · 10 -17 А⋅см-1

for fast neutrons at T = +20⁰C (no self-annealing)

Possible solution:• work at low temperature - (30-50)°C, detector leakage current doubles it’s value every 8 degrees;

•Detectors module design required very good thermo contact between Si-sensor and cooling plate for the excluding of the heating and thermo break down /3/

Scheme for the neutron leakage measuring (Top view. Detectors located at the beam axis)

Detector DEMON

lead assembly

1 2 3 4 513°

0°180°

24°

49°67°

90°113°

131°

156°

167°

detectors(TFBC & PSD)

«Quinta»

Window of beam entrance

Transmutation samples and activation detectors

Sections of natU

axis of the beam


Neutron fluxes (in the 1 deuteron) on the "Quinta" surface in various Ed

1 2 3 4 5 6 7 8 9 100E+00

1E-02

2E-02

3E-02

4E-02

5E-02

6E-02

7E-02

8E-02

9E-02

1E-01

0,66 GeV/A

1 GeV/A

2 GeV/A

4 GeV/A

position number

Flo

w n

/(sm

^2*d

)

Gomel, July 22 - August 2, 2013 d

0,66 1 2 4

GeV/A

11

79,6

9,4

9,6

81,6

8,8

8,9

82,3

8,8

8,2

80,5

11,3

0%

20%

40%

60%

80%

100%

1 2 3 4

Output of neutron leakage from the “Quinta" surface Experiment - a group of Zamyatin

Quinta

Detector Isomer

Protection

Pb

Measurement scheme with the “Demon”

Instrumental spectra of detector Demon



Recovered spectra of neutrons

50 100 150 200 250101

102

103

104

105

106

Neutr

on F

lux

E,MeV

1 GeV/N <E> = 111,9 MeV <M> = 1 2 GeV/N <E> = 114,8 MeV <M> = 2,5 4 GeV/N <E> = 118,3 MeV <M> = 4,6


1 10 100

0,8

1,2

1,6

2,0

2,4

2,8

3,2

3,6

4,0

4,4

4,8

0,8

1,2

1,6

2,0

2,4

2,8

3,2

3,6

4,0

4,4

4,8

2 GeV

4 GeV

R=

Gro

up4/

Gro

up5

En, MeV

System exp. data,238U+n

6 GeV

Comparison of neutron energy dependence of the weight ratios of 5-th to (4+3-th) DN groups from 238U(n,f)-reaction and similar values extracted from the DN time spectra measured in March 2011

Results&Analysis


Final storage and transmutation

Problem: Safe disposal of highly radioactive waste for more than 100 000 years

Goal:

Minimisation of the long-lived waste(plutonium and minor actinides, long-lived fission fragments)

Transmutation into shorter-lived nuclides

Integrated reaction capture and fission reaction rate versus energyin a FAST neutron energy spectrum


Minor actinides cross sections



Neutron capture – neutron induced fission

241Am(n,f)

241Am(n,)

thermal spectrum fast spectrum Neutron capture is dominating fission in a thermal spectrum

Fission is more probable than capture in a fast spectrum.


Ratio of neutron capture to fission

thermal spectrumfast spectrum

Schematic drawings of the box with actinide samples in the experimental window



1

2

3

4

5

6

7

8

9

10

R(n,f) = 5.83(75) E-26

R(n,f) = 1.67(20) E-26

R(n,f) = 3.35(40) E-26

R-f

acto

r/Y

ield

[1E

26 ·

d-1A

-1]

Identified radionuclide

1 GeV/A 2 GeV/A 4 GeV/A

237Np Fission

0 1 2 3 41

2

3

4

5

6

7

237Np(n,f)FP

237Np(n,f)FP per GeV/A

R-f

acto

r/Y

ield [

1E26

· d-1

A-1]

Deuteron beam energy [GeV/A]

237Np Reaction Rate Comparison

Eight fission products were identified in the 237Np sample. Reaction rates of all isotopes divided by the fission yield is presented in (a) and the averaged ratio as a function of deuteron beam energy and the same ratio related per GeV/A are presented in (b). Constant value of fission events per GeV/A can be seen within uncertainties.


The experimental results on the measurement of fission quantity and

production of Plutonium and Uranium 237


Reaction Rate Comparison Reaction Rate per GeV/A Comparison

Deuteron beam energy [GeV/A] Deuteron beam energy [GeV/A]

Experimental results on reactions in natU (left); the same dependence related per 1 GeV (right)


Ed = 2 ГэВ Ed = 4 ГэВ Ed = 8 ГэВ

Изотоп <R> <R>c <R> <R>c <R> <R>c

22Naa 1.37(27)E-28 - 3.47(69)E-28 - 2.34(47)E-27 -

22Nab 7.4(15)E-30 - 4.62(92)E-30 - 6.4(13)E-28 -

24Naa 1.77(8)E-28 - 3.30(40)E-28 - 1.55(19)E-27 -

24Nab 2.64(32)E-29 - 4.72(57)E-29 - 9.1(11)E-29 -

82Br 5.09(13)E-29 - 6.37(12)E-28 - 1.11(4)E-27 -

123I 1.68(8)E-29 1.26(16)E-29 3.46(38)E-29 3.30(51)E-29 - -

124I 2.98(16)E-29 2.42(15)E-29 6.65(45)E-29 6.37(81)E-29 1.05(18)E-28 0.91(17)E-28

126I 9.43(29)E-29 6.42(28)E-29 2.40(5)E-28 2.19(9)E-28 4.46(20)E-28 3.92(20)E-28

130I 4.59(10)E-27 - 1.07(2)E-26 - 1.84(4)E-26 -

The reaction rates for all product nuclei increase with energy of bombarding uranium assembly (target)

deuterons

The main findings on the project realization

The research of deeply subcritical electronuclear systems and features of its application to energy production and radioactive waste transmutation

• A significant value and increase in average energy of neutrons causing fission in limited model of central area of Active zones, with increase in beam energy point out that radioactive waste (RAW) may be used as reactor fuel on the base of nuclear relativistic technologies (NRT-reactor) with cardinal reducing amount of its complicated radiochemical recycling and burial of radioactive waste.

• Proportion of increase in fission quantity and production of Plutonium to increase in beam energy up to 8 GeV in conjunction with considerable increase in multiplicity and neutron leakage average energy, as well as value of energy, taken out (neutron leakage ~ 90%), bring out clearly the necessity to start carrying out of complex experiments at the “Buran” setup.

• The obtained results clearly prove the prospects of the NRT scheme. The final conclusions on its “starting” quantitative characteristics, working out of ways of the NRT-scheme and its elements application to nuclear and related industries will be possible only in course of carrying out complex experiments at the “Buran” setup.

• The “Buran” setup construction requires great financial, material and manpower costs, which are incommensurable to those of the “E and T - RAW” project.

However the results obtained by now, its degree of reliability, repeatability totally justify these costs. Gomel, July 22 - August 2, 2013

The main tasks for the activities of the “E&T-SNF” project with the target setup BURAN for 2014÷2016

The experiments carried out during the 1st stage of the project in 2011-2013 on the base of the target setup Quinta of the limited size allowed us to develop and test the main methods of measuring and data processing. As result of analysis of the experimental results described above the scientific and methodical programmes for measurements of the 2nd stage of the “E&T-SNF” project with the quasi infinite target setup BURAN were refined. It also gave an opportunity to estimate real terms and resources required for accomplishment of the programmes.

Consequently, the main tasks of the project aimed at experiments with the TS Buran for 2014-2016 are the following: Study of spatial distribution of neutron fields and their energy spectra inside and on the surface of the TS. Defining spatial distribution of densities of uranium nuclei fission inside the TS. Study of spatial distribution of 239Pu production and elimination (fission) dynamics and definition of equilibrium concentration for the given core configuration. Investigation of dependence of beam power amplification coefficient CAP on energy of bombarding particles (protons and deuterons) in order to find its optimal value for the given type of particle. Evaluation of velocity of recycling reactions of long-living isotopes composing RAW. Obtaining full set of experimental data required for verification and modification of existing theoretical models and transport codes, which can reliably describe and predict the properties of accelerator driven systems.

Conditions required for “E&T-SNF” project implementation The project scientific programme implementation is possible due to availability of the

unique target setup BURAN from depleted uranium (see Figures 29 and 30) at JINR. The uranium target cased in solid steel 10 cm thick frame has a mass of about 21 tons, a diameter of 1.2 m and a length of 1 m in relation to uranium.

As the TS BURAN was designed, produced and delivered to JINR for experiments at the Synchrophasotron more than 20 years ago its adjustment to carrying out experiments at the measurement hall in the Nuclotron F3 focus requires holding huge amount of designing and building and assembly works. Besides, elaboration of the TS central zones of different type made from uranium and lead is a complicated task.Gomel, July 22 - August 2, 2013

General view of the target setup BURAN at the transport-fixing platform.

The scheme of longitudinal section of the TS BURAN with the mounted central zone (left) and general view photo (right).

Protons DeuteronsЕр(d), GeV 1 6 12 1 6 12

Total multiplicity of neutrons 126 770 1450 125 794 1455

Reactions number (n,γ) 70 440 826 70 452 837

Reactions number (n,f) 16 100 183 15 100 183

CAP = Еtotal/Ep(d) 3.82 3.75 3.5 3.82 3.85 3.55

Integral characteristics of the target setup BURAN bombarded with proton and deuteron beams calculated per 1 incident

particle.

PROTONS DEUTERONS

Ер(d), GeV 1 6 12 1 6 12

Coordinates

Fe-1 3.2 10 21 3.2 11 17

U-2 8 30 55 8.1 29 48

Fe-3 0.03 1 1.8 0.03 0.95 2.4

U-4 0.22 6 11 0.2 6 15

Fe-6 0.16 1.2 2 0.16 1.8 2.1

U-7 1 7.5 13 1.2 7.5 14

Total 3.34 13 24 3.34 13 22

Neutron leakage from the surface of the target setup BURAN per 1 incident particle.


Thank you for attention

Gomel, Belarus, July 22 - August 2, 2013

the actual problems of microworld physics the actual problems of microworld physics gomel, belarus,...

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